bostonbiker

Is it all right?

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by

jsallen
in

At the Boston Bicycle Safety Summit, February 23, 2016, in a small breakout group, Cyclist Jonathan Traum drew a sketch like this:

Right-hook conflict illustrated
Right-hook conflict illustrated

(Thanks to John Schubert for this version, which looks like Traum’s, only neater.)

Traum indicated that the right-hook conflict shown in the illustration was a serious problem, with bike lanes which encourage bicyclists to overtake on the right.

MassDOT engineer Lou Rabito replied with by-the-book advice as in the AASHTO (American Association of State Highway and Transportation Officials) guide to bicycle facility design, that it isn’t OK with a right-turn-only lane, but it is OK with a lane which carries both right-turning traffic and through traffic.

Comments

6 responses to “Is it all right?”

  1. Charlie Avatar
    Charlie

    I keep hearing over and over again from you and others that bike lanes create additional right hook dangers. But what would you propose as a solution to that? (And don’t say not providing bike lanes at all and advising bicyclists to take the lane. That is not a practical nor realistic solution.)

  2. jsallen Avatar
    jsallen

    Charlie, as to what is not practical and realistic, let’s make a distinction:

    Saying out of the coffin corner is not the same as not building bike lanes, or not riding in them, providing that they are well-designed and located. But most Boston-area bike lanes are unfortunately in the door zone. Doorings are the single largest cause of bicycle crashes reported to Boston police. Most Boston-area bike lanes lead into the coffin corner at intersections, and coffin-corner crashes are the single largest cause of cyclist fatalities in the Boston area.

    What do you think is practical and realistic about luring bicyclists into these traps, and not practical and realistic about avoiding them, as I have successfully done for 40 years, in a number of ways including route choice, communicating with other road users using signaling and lane position (not just baldly “taking the lane”), using a rear-view mirror as a tool to improve situational awareness and dispel fear; also advocating for infrastructure approaches which actually work (a topic for a longer post, so, see for example, https://john-s-allen.com/bostonbiker/2013/01/30/connecting-the-boston-university-campus/ and the discussion at the end of https://john-s-allen.com/blog/?p=5750. What solutions can *you* propose?

  3. Charlie Avatar
    Charlie

    The best solution to providing a facility that attracts many more bicyclists but also reduces the right hook risk that traditional bike lanes pose is to provide physically separated bike lanes with protected intersections. It gives bicyclists a dedicated space but makes them visible at intersections. The protected intersections force vehicles to turn BEFORE reaching the bike lane crossing, thereby making it easier for drivers to see and yield to bicyclists.

    1. jsallen Avatar
      jsallen

      First of all, Charlie, thanks for acknowledging that traditional bike lanes pose a right-hook risk. I’ve been saying that for 25 years, based on solid evidence, since Cambridge began installing them — while other advocates including you were relentlessly promoting them. Now, oh look, they’re risky. And now, in your words, “[T]he best solution to providing a facility that attracts many more bicyclists but also reduces the right hook risk that traditional bike lanes pose is to provide physically separated bike lanes with protected intersections.”

      And really, “best”? Are these turn-and-yield intersections better then than grade separations, which completely eliminate the conflict? The Netherlands is constructing these and we’ve seen publicity about some very fancy and expensive ones. Of course, bicyclists have more political clout in the Netherlands, and we’re seeing only the most impressive installations, but I think that it’s fair to ask whether the fundamental approach in promoting bicycle infrastructure should be to keep the eyes on the prize, or should be a stepwise, opportunistic approach, promoting and adopting different treatments as politics allows, then discarding each in turn as problems reveal themselves in practice, and the constituency builds to take the next step.

      A protected movement, as the term is used in traffic engineering, is one where all conflicting traffic is held back by a traffic signal, not one where drivers have to look and yield. You avoided using the opinion-loaded term “protected” in describing the bike lane, but you use it where it actually becomes inaccurate, at the intersection.

      Eyes on the prize, but what is the prize? It bothers me to be told that there is a single best solution. Solutions differ when competing factors — the safety and mobility of the different types of users, and expense — are taken into account. You and I and many others are advocating together for grade separations where the Paul Dudley White path crosses intersections along the Charles River, but it’s a hard sell, given the expense, even at these very heavily-traveled locations. Your proposed turn and yield solution has been heavily promoted recently — see my blog post about it, and commenters' responses — and it could be preferable under some conditions: Dutch research shows it to be safer when the path crossing is 2 to 5 meters from the roadway — but it takes a lot of space, which may not be available, creates confusing conflicts between bicyclists and pedestrians, and also reduces throughput at intersections when turning motorists queue up before the turn. Promotions invariably avoid these issues.

      Interestingly, Denmark takes the opposite approach, bringing the separate bikeway up to the side of the roadway at intersections, and Germany is turning away from separate bikeways to install buffered bike lanes — see the last few pages of Paul Schimek’s study of bicycle crashes. (Open it in PowerPoint. Keynote on the Mac, or LibreOffice Impress so you can see the speaker notes as well as the slides.) Separate traffic signal phases and prohibition of right turn on red are another possibility, and produce a truly protected movement, though at the expense of delay. On small streets with low traffic volume and slow traffic, only neighborhood greenway treatments are warranted, to keep down the speed and volume of motor traffic. This is also becoming popular in the Netherlands, under the name “unbundling.” Last but not least, confident and skillful bicyclists will prefer to avoid the delay caused by all of these treatments other than the grade separation, and ride in the stream of mixed traffic. Overconfident, unskilled cyclists, impatient with delays, will become opportunistic and make unpredictable and hazardous moves. Licensing and law enforcement against motorists also is very lax. Education and law enforcement also are part of the picture.

      What’s the saying? — “If your only tool is a hammer, every problem looks like a nail…”

  4. Charlie Avatar
    Charlie

    We can only really advocate for solutions that have a reasonable chance of actually being implemented.

    We’ve been advocating for striped bike lanes because that was the best tool we had for busy arterial streets. Finally, the US has guidance on separated/protected bike lanes, so we can reasonably advocate for those as well.

    Grade separation of course solves the intersection issue, but that is a very expensive and often undesirable solution given how much land it requires.

    I totally agree with you that there is no one best solution for all streets. I certainly agree with your views that bicycle boulevards should be part of the bicycle network, and that on quieter, narrower, low volume streets, bike lanes are often not needed nor desired. When I refer to a “best” solution, I’m mainly referring to urban arterial streets where buildings abut the street and we don’t have a ton of extra room to work with.

    I have seen signals to protect bicycles from right turning traffic, but I’ve also seen it where there are protected intersections where the bike lane pulls away and turning vehicles are expected to yield once they have begun their turn. I think it really depends on the context and amount of turning traffic as to which solution is better in specific cases.

  5. Jack Hughes Avatar
    Jack Hughes

    When you refer to a “‘best’ solution,” Charlie, it might help for you to clearly define the problem(s) the solution is meant to address.

    From the context of your comments, it seems as though you have presupposed that the bicycle lane or the so-called protected bicycle lane is a solution to something, even if it creates more hazard than it mitigates. If the problem is defined as helping potential but uncertain cyclists overcome predominate fear of being hit from behind while cycling, the solution of segregated facilities presents itself naturally. If the problem is defined as what to do to mitigate the proven increased hazzards at intersections that solution presents, not segregating the cyclists in the first place really does present itself as a practical solution. Also presenting itself is the idea of separate signal phases for the two modes of traffic at the intersections (reducing the potential for conflicts while creating another problem to solve of increased delay for all users) and the idea of de-segregating the two modes with a mixing zone well before the intersection (reducing the potential for conflicts while retaining what benefits segregation may have where intersections are not found).

    You are right to consider that each location presents different problems to solve. And you seem to realize also that sometimes “not providing bike lanes at all and advising bicyclists to take the lane” is indeed a practical and realistic “solution.” Better behavior solutions often beat infrastructure “solutions” that lure (or worse, force!) cyclists into danger.

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